ContextAtrial fibrillation is the most common arrhythmia in elderly persons
and a potent risk factor for stroke. However, recent prevalence and projected
future numbers of persons with atrial fibrillation are not well described.ObjectiveTo estimate prevalence of atrial fibrillation and US national projections
of the numbers of persons with atrial fibrillation through the year 2050.Design, Setting, and PatientsCross-sectional study of adults aged 20 years or older who were enrolled
in a large health maintenance organization in California and who had atrial
fibrillation diagnosed between July 1, 1996, and December 31, 1997.Main Outcome MeasuresPrevalence of atrial fibrillation in the study population of 1.89 million;
projected number of persons in the United States with atrial fibrillation
between 1995-2050.ResultsA total of 17 974 adults with diagnosed atrial fibrillation were
identified during the study period; 45% were aged 75 years or older. The prevalence
of atrial fibrillation was 0.95% (95% confidence interval, 0.94%-0.96%). Atrial
fibrillation was more common in men than in women (1.1% vs 0.8%; P<.001). Prevalence increased from 0.1% among adults younger than
55 years to 9.0% in persons aged 80 years or older. Among persons aged 50
years or older, prevalence of atrial fibrillation was higher in whites than
in blacks (2.2% vs 1.5%; P<.001). We estimate
approximately 2.3 million US adults currently have atrial fibrillation. We
project that this will increase to more than 5.6 million (lower bound, 5.0;
upper bound, 6.3) by the year 2050, with more than 50% of affected individuals
aged 80 years or older.ConclusionsOur study confirms that atrial fibrillation is common among older adults
and provides a contemporary basis for estimates of prevalence in the United
States. The number of patients with atrial fibrillation is likely to increase
2.5-fold during the next 50 years, reflecting the growing proportion of elderly
individuals. Coordinated efforts are needed to face the increasing challenge
of optimal stroke prevention and rhythm management in patients with atrial
fibrillation.

https://jamanetwork.com/journals/jama/articlepdf/193807/jcc10004.pdf

Prevalence of diagnosed atrial fibrillation in adults: national implications for rhythm management and stroke prevention: the AnTicoagulation and Risk Factors in Atrial Fibrillation (ATRIA) Study.

Background—Atrial fibrillation (AF) causes substantial morbidity. It is uncertain whether AF is associated with excess mortality independent of associated cardiac conditions and risk factors. Methods and Results—We examined the mortality of subjects 55 to 94 years of age who developed AF during 40 years of follow-up of the original Framingham Heart Study cohort. Of the original 5209 subjects, 296 men and 325 women (mean ages, 74 and 76 years, respectively) developed AF and met eligibility criteria. By pooled logistic regression, after adjustment for age, hypertension, smoking, diabetes, left ventricular hypertrophy, myocardial infarction, congestive heart failure, valvular heart disease, and stroke or transient ischemic attack, AF was associated with an OR for death of 1.5 (95% CI, 1.2 to 1.8) in men and 1.9 (95% CI, 1.5 to 2.2) in women. The risk of mortality conferred by AF did not significantly vary by age. However, there was a significant AF-sex interaction: AF diminished the female advantage in survi...

Impact of Atrial Fibrillation on the Risk of Death The Framingham Heart Study

Objective. —To determine the independent risk factors for atrial fibrillation. Design. —Cohort study. Setting. —The Framingham Heart Study. Subjects. —A total of 2090 men and 2641 women members of the original cohort, free of a history of atrial fibrillation, between the ages of 55 and 94 years. Main Outcome Measures. —Sex-specific multiple logistic regression models to identify independent risk factors for atrial fibrillation, including age, smoking, diabetes, electrocardiographic left ventricular hypertrophy, hypertension, myocardial infarction, congestive heart failure, and valve disease. Results. —During up to 38 years of follow-up, 264 men and 298 women developed atrial fibrillation. After adjusting for age and other risk factors for atrial fibrillation, men had a 1.5 times greater risk of developing atrial fibrillation than women. In the full multivariable model, the odds ratio (OR) of atrial fibrillation for each decade of advancing age was 2.1 for men and 2.2 for women (P Conclusion. —In addition to intrinsic cardiac causes such as valve disease and congestive heart failure, risk factors for cardiovascular disease also predispose to atrial fibrillation. Modification of risk factors for cardiovascular disease may have the added benefit of diminishing the incidence of atrial fibrillation. (JAMA. 1994;271:840-844)

https://jamanetwork.com/journals/jama/articlepdf/367563/jama_271_11_036.pdf

Independent risk factors for atrial fibrillation in a population-based cohort. The Framingham Heart Study.

The prevalence of atrial fibrillation (AF) is related to age. Anticoagulation is highly effective in preventing stroke in patients with AF, but the risk of hemorrhage may be increased in older patients. We reviewed the available epidemiologic data to define the age and sex distribution of people with AF. From four large recent population-based surveys, we estimated the overall age- and gender-specific prevalence of AF. These estimates were applied to the recent US census data to calculate the number of men and women with AF in each age group. There are an estimated 2.2 million people in the United States with AF, with a median age of about 75 years. The prevalence of AF is 2.3% in people older than 40 years and 5.9% in those older than 65 years. Approximately 70% of individuals with AF are between 65 and 85 years of age. The absolute number of men and women with AF is about equal. After age 75 years, about 60% of the people with AF are women. In contrast to people with AF in the general population, patients with AF in recent anticoagulation trials had a mean age of 69 years, and only 20% were older than 75 years. The risks and benefits of antithrombotic therapy in older individuals are important considerations in stroke prevention in AF. (Arch Intern Med. 1995;155:469-473)

https://jamanetwork.com/journals/INTEMED/articlepdf/620157/archinte_155_5_005.pdf

Prevalence, Age Distribution, and Gender of Patients With Atrial Fibrillation: Analysis and Implications

prevalence of atrial fibrillation (AF) is related to age. Anticoagulation is highly effective in preventing stroke in patients with AF, but the risk of hemorrhage may be increased in older patients. We reviewed the available epidemiologic data to define the age and sex distribution of people with AF. From four large recent population-based surveys, we estimated the overall age- and gender-specific prevalence of AF. These estimates were applied to the recent US census data to calculate the number of men and women with AF in each age group. There are an estimated 2.2 million people in the United States with AF, with a median age of about 75 years. The prevalence of AF is 2.3% in people older than 40 years and 5.9% in those older than 65 years. Approximately 70% of individuals with AF are between 65 and 85 years of age. The absolute number of men and women with AF is about equal. After age 75 years, about 60% of the people with AF are women. In contrast to people with AF in the general population, patients with AF in recent anticoagulation trials had a mean age of 69 years, and only 20% were older than 75 years. The risks and benefits of antithrombotic therapy in older individuals are important considerations in stroke prevention in AF. (Arch Intern Med. 1995;155:469-473)

Prevalence, Age Distribution, and Gender of Patients With Atrial Fibrillation

Objectives: The report describes the strategic design, steps to full implementation and outcomes achieved by the Western Australian Data Linkage System (WADLS), instigated in 1995 to link up to 40 years of data from over 30 collections for an historical population of 3.7 million. Staged development has seen its expansion, initially from a linkage key to local health data sets, to encompass links to national and local health and welfare data sets, genealogical links and spatial references for mapping applications. Applications: The WADLS has supported over 400 studies with over 250 journal publications and 35 graduate research degrees. Applications have occurred in health services utilisation and outcomes, aetiologic research, disease surveillance and needs analysis, and in methodologic research. Benefits: Longitudinal studies have become cheaper and more complete; deletion of duplicate records and correction of data artifacts have enhanced the quality of information assets; data linkage has conserved patient privacy; community machinery necessary for organised responses to health and social problems has been exercised; and the commercial return on research infrastructure investment has exceeded 1000%. Most importantly, there have been unbiased contributions to medical knowledge and identifiable advances in population health arising from the

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A decade of data linkage in Western Australia: strategic design, applications and benefits of the WA data linkage system

Age related changes in drivers' crash risk and crash type

Prospective data from Busselton, Western Australia, collected during triennial surveys from 1966-81 with follow-up of subjects to 1983, showed that atrial fibrillation (AF) was frequent in elderly people and associated with increased mortality. Of 1770 people aged over 60 years, 40 were in atrial fibrillation when first seen and a further 47 developed it during follow-up. Atrial fibrillation was positively associated with angina, history of a myocardial infarction and left bundle branch block. Relative mortality in those with atrial fibrillation compared with those without it, was 1.92 for all causes, 1.82 for death from cardiovascular causes (excluding stroke) and 3.78 for deaths from stroke, after adjustment by proportional hazards regression for confounding effects of age, sex, history of a myocardial infarction, an abnormal electrocardiogram, angina, cholesterol level systolic blood pressure and Quetelet's Index (weight/height2). The excess relative mortality declined with increasing age for both women and men. This raised relative mortality remained constant with time from the first detection of AF for all causes and cardiovascular causes but appeared to increase with time from detection for stroke death. The risk of death from stroke was greatest in the younger women. The observed risk of death from stroke in patients with AF suggests that anticoagulant use should be considered in selected patients.

Diana L. Rosman

Papers

A decade of data linkage in Western Australia: strategic design, applications and benefits of the WA data linkage system

Age related changes in drivers' crash risk and crash type

Atrial fibrillation and mortality in an elderly population.

A comparison of hospital and police road injury data

Public good through data linkage: measuring research outputs from the Western Australian Data Linkage System